Serotonergic mechanisms have been implicated in central hypoventilation syndrome. Serotonergic neurons are in an area anatomically close to areas of cardiorespiratory control. We hypothesize that improvement in oxygenation in an adolescent with central hypoventilation was secondary to the addition of fluoxetine. Testosterone administration is believed to have an adverse influence on upper airway patency during sleep. We hypothesize these effects will be obviated by continous delivery of testosterone via a patch. Addition of fluoxetine to his regimen averted the need for xracheostomy, withdrawal of fluoxetine resulted in deterioration of his oxygenation. Testosterone administration by patch did not adversely affect upper airway patency. Study completed.